Asset allocation...is the overwhelmingly dominant contributor to total return.
--Gary Brinson, Brian Singer and Gilbert Beebower
Most investors concentrate on trying to choose the best stock and pick the perfect moment to buy or sell. It's a waste. What really matters to your long-term returns is asset allocation--that is, how you split up your portfolio.
Since researchers dropped this bombshell 20 years ago, experts have debated the size of the asset-allocation factor. Some say it accounts for 40% of the variation in investors' returns; others (like the original researchers) say 90%. But no one refutes that it's major. For help getting the best mix for your goals and risk tolerance, see the Asset Allocator tool.